Try finding (or making) a pinhole aperture for your glasses like the one below. I believe the hole diameter is 2mm. My eyes are like yours and it really sharpened up the rear sight on my AK, amazingly so. The design allows you to reposition the aperture for various situations as needed.

Here's one that's homemade... he used a 5/64" drill bit which, ironically is almost exactly 2mm.